James dougherty



J. DOUGHERTY;

GUPoLA .Pimmel-..-

10.641345 Patented May-14, 1867.

JAMES noUeIIEETr, or PHILADELPHIA, PENNSYLVANIA.

Letters Patent No. 64,645, dated May 14, 1867.

IMPROVEMENT IN GUPOLA FURNAGES.

@te tlgehnlr tuant tf1-iu tips): trttrtsjrttnt mit making nut nt tige smut TO ALL WHOM II MAY CONCERN:

Be it known that I, JAMES DOUGIIERTY, of Philadelphia,Pennsylvania, have invented certain improvements in Furnaces or Cupolas, and I do hereby declare the following to 'be a full, clear, and exact description of the same. l

My invtntion Consists,'first, of a cupola or blast furnace, the interior f the lower portion of which is composed of a chamber with vertical walls, and above the latter a basiniike chamber contracted at the top, all substantially as described hereafter, this form o'f furnace being considered best adapted for the rapid melting of metals and reduction of ores; second, of a system of tuyeres having openings so arranged as to' discharge a blast 'of greater volume below than above; third, of certain air openings arranged in respect to an annular projection in the furnace, as described hereafter, so that jets of air maybe directed on to theq rising products of combustion. 'I

In order to enable-others skilled in the art to make and use my invention, I will now proceed to describe its construction and operation, reference being had to the accompanying, drawing, which forms a part of this specification, and in which- Figure 1 is a vertical section of my improved furnace or cupola; and

Figure 2, a. sectional plan on the line 1 2, iig. 1.

Similar letters refer to similar part-s throughout the several views.

A represents the outer sheet-iron casing of the cupola, B the fire-brick lining, and the l plate on which the cupola is built, and which is supported on columns (not shown in the drawing) lin the usual manner. From the base D to the linen: the interior of the furnace is contracted, so as to form .the cylindrical chamber G, and from this line :r upwards the interior is graduallyenlarged, to be gradually reduced as it approaches the line y, where there is a. prominent annular projection, m, fromuthc walls, so that between the lines a: andyis formed a basin, F, of thc shape, or approximating to the shape, represented in the drawing. From the line y to the' line t theinterior of the cupola is abruptly enlarged, and above -the latter line assumes the cylindrical form represented until it approaches the usual chimney or stack with which the cupola is surmounted. Bet-Ween the Alining B of the cupola and the outer casing of the saine, and adjacent to the cylindrical chamber G,'is formed ,it-hev annular chamber 'which receives the blast and distributes the sume to the several tuyeres. In the present .instance there are eight tuyercs,four designated by the letter I-I, and four by the letter I. These tuyeres consist of cast-iron blocks arranged'at equal distances apart, and built in the tire-brick lining. Thelblocks II are arranged between and are situated somewhat lower than the blocks I, and the holes in the latter differ very materially in shape from those of the former, the holes t inthe blocks II being roundand inclined downwards from the blast-distributing chamber, as shown in the drawing, while the holes the blocks Iva-rc elongated vertically, andare widerbelowthan above. It 'will be evident that 'the blast admitted to the cylindrical chamber 4Gr will extend in altitude from the point q to the point @but that the blast will be of much greater volume below than above, where it haste pass through the contracted upper ends of the elongated openings z' of the blocks I, whereas it has an exit' below both through the larger round holes 7L of the tuyeres or blocks H, aswell as through the enlarged lower ends of the said elongated openings. This vmode of distributing the blast into the chambr G of the cupola has been found most eiicient in practice. 'lhc blast-distributing chamber v com? inunicatcs through an annular' passage,f, with a small distributing chamber, J, which is situated atthe same height as, alud adjacent to, the projection m of the brick lining, and` the chamber J communicates withA the hasinhkc chamber F of the cupola through a number of small inclined passages, fw, (there are sixteen vin the present instance,) terminating a short distaiice below the said projection m of the lining B, hence. a number of small jets ot` air must bc projected on to,` the fuel, effecting a thorough consumption ofthe unconsumcd products of combustion, and rendering material aid-.in reducing ores or metals. The cupola is furnished with the'usual tapping hole, shown by dotted lines at 7c, and with ablas't pipe, Z, through which air is forced into the distributor' E. Although I have illustrated and described the inteririof the furnace as being circular, it is not essential in the carrying out of my invention that this form should be preserved, asthc interior may be of an oblong or oval forn, the tuyeres and blast-distributing' chambers being arranged accordingly, nor -is it imperative .that there should he a communicatiom bctween'the two blast-distributing chambers E and J, as the-lutter muy receive the compressed air from independent pipes. The tuyere openings h and a', too, may bemodied in form, providing they deliver the blast in a. greator'volume below than above.

I do not .desire to clnimbr'oodly inject-ing jets of a-ir on to'the fuel or products of combustion in furnaces. ne this has been heretofore done, but claim es my invention, nud desire to secure by Letters Patent- 1. Aicupolqtor blast furnace, the interior of the lower portio of which is composed of the chamber G,

with vertical walls, and above the latter the basin-like chamber F, contracted nt the top, all' sllbstontiell),t as

specified. y

2. The combination, with n cupola. or blnstfurnuce, of a sy'etem of tuyeres having openings so arranged ns to discharge e blo'st of greater volume below than above, n s set forth. I

3. The oir openings w, arranged in respect to the projection m and basin-like chamber F, as described. In testimony whcreeflhnve signed my nome to this specification in the presence of two subscribing witnesses.

JAS. DOUGHERTY.

Witnesses ROBERT I-IUTcnINsoN, H. Howsokv.- 

